Detection of immune checkpoint molecules by deglycosylation

Abstract

Provided herein are methods of detecting glycosylated proteins, such as immune checkpoint proteins. Further provided are methods of treating cancer, such as by administering immune checkpoint inhibitors.

Description

[0001]This application claims the benefit of U.S. Provisional Patent Application No. 62 / 681,929 filed Jun. 7, 2018, the entirety of which is incorporated herein by reference.BACKGROUND1. Field[0002]The present invention relates generally to the field of molecular biology. More particularly, it concerns the detection of glycosylated proteins, such as immune checkpoint molecules.2. Description of Related Art[0003]The Food and Drug Administration (FDA) approval of immune checkpoint inhibitors has dramatically changed treatment paradigms for patients with advanced-stage or metastatic non-small cell lung cancer (NSCLC). Despite significant improvements in survival, the majority of NSCLC patients fail to respond to checkpoint inhibitors, notably antibodies targeting programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1), and uncertainties remain regarding how best to use these therapies in clinical practice. Given the risk of immune-related and other adverse effects associated wi...

AI Technical Summary

Benefits of technology

The present patent provides an in vitro method for detecting the level of an immune checkpoint protein in a sample, such as PD-L1, PD-L2, TIM-3, B7-H3, B7-H4, VISTA, CD40, PD-1, CTLA-4, or OX-40L. The method involves obtaining a fixed sample, such as saliva, blood, urine, normal tissue, or tumor tissue, and contacting it with an anti-immune checkpoint protein antibody. The sample can be a formalin fixed sample or paraformaldehyde fixed sample. The fixed sample can be isolated from saliva, blood, urine, normal tissue, or tumor tissue. The method can be performed using immunoblotting, immunohistochemistry, ELISA, or immunofluorescence. The immune checkpoint inhibitor can be administered to a subject with an increased level of the immune checkpoint protein to treat cancer or other immune checkpoint-associated diseases. The patent also provides a pharmaceutical composition comprising an immune checkpoint inhibitor for use in treating cancer in a subject with an increased level of the immune checkpoint protein.

Problems solved by technology

Despite significant improvements in survival, the majority of NSCLC patients fail to respond to checkpoint inhibitors, notably antibodies targeting programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1), and uncertainties remain regarding how best to use these therapies in clinical practice.

However, there are limitations to using PD-L1 as a predictive biomarker in NSCLC due to a lack of accurate diagnostic assays that can measure PD-L1 expression.

However, there is no direct biomarker available for anti-PD-L1 therapy since PD-L1 IHC staining readout is not associated with patient response after anti-PD-L1 therapy, where it remains unclear if this discrepancy comes from certain unknown biological mechanism or technical issue for detection (Garon et al.

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